Insulator for electric overhead construction



(No Model.)

11. P. BALL. INSULATOR FOR ELECTRIC OVERHEAD GONSTRUUTION.

110. 530,498. Patented D6G. 11,1894.

WH'NEEEEE- UNITED STATES PATENT OFFICE.

HENRY PRICE BALL, OF BRIDGEPORT, CONNECTICUT, ASSIGNOR TO THE GENERAL ELECTRIC COMPANY, OF BOSTON, MASSACHUSETTS.

INSULATOR FOR ELECTRIC OVERHEAD CONSTRUCTION.

SPECIFICATION forming part of Letters Patent No. 530,498, dated December 11, 1894. Application filed June 28, 1894. Serial No. 515,909. (No model.)

To aZZ whom it may concern:

Be it known that I, HENRY PRICE BALL, a citizen of theUnited States,residing at Bridge port, in the county of Fairfield, State of Connecticut, have invented certain new and useful Improvements in Insulators for Electric Overhead Construction, of which the following is a specification.

My invention relates to strain insulators for electric overhead construction; and has for its object to provide an eflicient form or in sulator of great strength and one easily and cheaply made. To these ends I arrange two eye-bolts or parts, preferably formed of mild steel, although they may be made of any other metal easily cast, pressed or wrought into shape, and I arrange these parts so that one may be introduced within the other, and then partly rotated so that it cannot be withdrawn by a direct pull. The whole structure Iinclose in a mass of insulating material, which is formed between the two parts taking the strain as well as upon the outside thereof, and is preferably united with the parts by heat and pressure so that the whole structure is practically integral. I prefer to make it in spherical form, although this is immaterial, and any other shape may be selected by the engineer.

The accompanying drawings show an embodiment of my invention, wherein- Figure 1 is an elevation; Fig. 2, a vertical section, and Fig. 3 a vertical section on the line 3-3 of Fig. 2 of my improved insulator, which I prefer to call a ball-insulator.

A is the body of insulating material inclosing the parts B, C. The part or eye-bolt B is formed with the portion B of conoidal form, the base of the cone being an ellipse. Two difierent sections are shown, the longitudinal section being shown in Fig. 2, the vertical or cross section being shown in Fig. 3. The cooperating part or hold-piece C is formed with a conoidal flange, also with elliptical base, the flange being lettered C'. Thus one diameter of the flanged opening will be greater than the other. The inner edge of the flange is brought down as close to the bolt B as is possible allowing for the thickness of the insulating material at this point. A screw-thread ating is formed in the shank of the part C and in this thread an eye-bolt B is inserted.

To assemble the parts herein pointed out, the eye-bolt B is passed within the flange C and given a quarter turn. The insulating material is then pressed within the parts holding them in position and the whole is then incased in a globule of insulating material,and formed into shape in a press under heat and great pressure. The whole thus forms a compact and efficient strain insulator, its strength being limited by the tensile strength of the iron and by the crushing strength of the insulating material formed between the two co-operparts.

For high potential lines where the risk of leakage is greater 1 may make the insulator of larger size and put a greater body of insulating material between the co-operating parts. I may also tap a central opening in the eyebolt B as shown at B which I may fill with insulating material to prevent the danger of short-circuit between the parts.

The use and operation of this device will be readily understood by those skilled in the art.

What I claim as new, and desire to secure by Letters Patent of the United States, is

1. As a new article of manufacture, a strain insulator comprising a part provided with a flange having one diameter of its opening greater than the other, an eye-bolt having an engaging part formed with one diameter smaller than the other, the two parts being arranged and adapted, as herein described, to engage, when the longer diameter of the eyebolt is transverse to the short diameter of the flange, and insulating material securingthe parts together and insulating them from each other.

2. As a new article of manufacture, a strain insulator comprising aflanged part, as C, the flange being made in conoidal form with an elliptical base, an eye-bolt as 13' having a similar engaging part adapted to be inserted within the flange and to engage therewith by a partial revolution, and insulating material, formed around and between the two engaging parts, arranged to insulate themfrom one another and to secure them rigidly in position.

3. As a new article of manufacture, a strain insulator comprising a flanged part, as O, the a partial revolution, and insulating material 10 flange being of conoidal form having an ellipformed around and between the engaging tical base,a thread in the shank of such flanged parts.

part, and an eye-bolt as B engaging with the In witness whereof I have hereunto set my thread, a second eye-bolt as B having a part hand this 25th day of June, 1894. adapted to engage with the flange, such part being also of conoidal form and having an elliptical base, the flange and second eye-bolt being arranged to engage with each other by HENRY PRICE BALL. Witnesses:

W. H. Mom, 0. E. CARPENTER. 

